Running a GPS on my snowmobile battery

I want to hook up a Lowrance Elite 7 to my sled battery. Will this drain the battery too fast if I leave the GPS on after the sled is shut off? Do I need to wire it to a separate battery just for the GPS?

Look up your amp draw on the GPS, figure out how long you will be sitting, see the battery capacity and you can calculate how long before you drain the battery. Myself, I would not recommend it. I know I will often sit in one spot ice fishing if the fish are there for hours. I believe on all the lowrance's, you can see your voltage. To monitor, you could have that on your screen as an option. If you start to drop around 12 V, then fire up your motor would be another option. This is all assuming you don't have a way to fire up your sled other than the battery.